Medical device with hydraulically movable parts

ABSTRACT

A medical device has hydraulically movable parts steered by instrumental valves and a central steering device which includes steering members for actuating the valves and connecting elements between the steering members and the valves. The invention is particularly characterized in that as means for transmitting pressure necessary for actuating the valves a flowing medium is used.

iinited Mates Patent 1191 Warden et al. Nov. 5, 1974 1 MEDICAL DEVICEWITH 2,717,107 9/1955 Moletz 91/461 x HYDRAULIC ALLY MOVABLE PARTS2,794,694 6/1957 Fullwood' 269/325 2,994,443 8/1961 Gordon 254/10 R X[75] Inventors: Hans Erlk Warden, pp 3,041,12 6/1962 Burzlaff....269/325 Vasby; Frank Kindvall, Danderyd; 3,206,188 9/1965 Douglass...269/325 Carls Oloi Berg, Stocksund; Bengt 3,220,318 11/1965 McGuire 191/461 Sedell, Nacka, all of Sweden 3,473,024 10/1969 Feiertag 269/323 X[73] Assignee: Siemens Alrtiengesellschaft,

Erl g n, Ge y Primary Examiner-Roy Lake 2 d: 26 7 AssistantExaminer-Mark S. Bicks [2 1 le June 19 3 Attorney, Agent, orFirm-Richards & Geier [21] Appl. No.: 373,814

[30] Foreign Application Priority Data [57] ABSTRACT July 3, 1972Germany 2232553 A medical device has hydraulically movable parts [52]US. Cl. 269/323 t d b in t mental valves and a central steering [51]Int. Cl A61g 13/00 de i e whi h includes steering members for actuatingField of Search 427, the valves and connecting elements between thesteer- 254/10 R, 10 B, 10 C, 124; 269/322, 323, ing members and thevalves. The invention is particu- 324, 325 larly characterized in thatas means for transmitting pressure necessary for actuating the valves aflowing [56] References Cited di m is used,

UNITED STATES PATENTS 2,217,783 10/1940 Bell 269/325 9 Claims, 5 DrawingFigures 2] 2U 22 F l I 1...; 4

X 16 l is operating table.

' ing device.

' MEDICAL DEVICE'WITH HYDRAULlCALL-Y.

I 1 MOVABLE PARTS g I I This invention relates to a medical device withhydraulically Ymovable parts steered by instrumental valves and acentral steering device'which includes steering members-for actuatingthe valves and'connecting elements between thesteering members and thevalves. t I t In known hydraulicallyactuated operating tables of thistype the valves of the hydraulic system are located in a centralsteering device (US. Pat. No. 3,28l,l4l This steering device is usually,mounted upon a swingable arm extending over the operating tableso thatthe persons working at the operating table should not be disturbed bythe person actuating the movements of the The drawbacksof this knowntable consist primarily in that due to the large sizes of the oil hoseof the hydraulic operating system which are required by the high 1 oil'pressure and the comparatively large flowing I masses, theconn'ectingconduits become strong and unis difticult-to move the centralsteerflexible andthus it lnanother known hydraulically movable-operatingtable electrical actuating circuits are used for steering the valves.The drawback. involved in using electrical circuits in an operating roomconsists in that electrical contacts must be incased safely againstexplosion due to the danger of explosion of the narcotic gas located inthe operating room. These protecting devices are expensiveand their usedoes not completely eliminate th danger of explosion but merely reducesit.

An object of the present invention is to provide an actuating device forthe hydraulic valves which will not produce any danger of explosion evenin contact with narcotic gas and furthermore, wherein the connectingelements between the valves of the operating table and the central,steering device are thin, light and flexible.

Other objects of the present invention will become apparent in thecourse of the following specification.

In the accomplishment of the objectives of the present invention it wasfound desirable to use a flowing medium as means for transmittingpressure required for the actuation of the instrumental valves. When agas is used as the flowing medium, for example, compressed air, therequired dimensions of the connecting elements can be kept so small thatthey can be compared to a conducting wire for low current. These thintubes provide a connection between the operating table and the steeringdevice which is absolutely safe against explosion and, in addition,which is easily movable.

In a preferred embodiment of the present invention it is suggested toprovide positioning valves connected in parallel with instrumentalvalves for automatically determining specific positions (basicpositions) of the patient supporting plate. These positioning valves areswitched on by a separate steering member or by several steering memberscommon to them and they are switched off in the predetermined positionof the patient supporting plate by studs or the like located upon partspertaining to the corresponding positioning valves. This arrangementprovides that specific locations of the supporting plate which areconsidered particularly advantageous by operating doctors can be foundimmediately upon the central steering devicebyactuating a switch key ofa steering member.

According to a further embodiment of the present invention it issuggested to provide means switchable by further steering members whichshort circuit in such manner valves provided for the movement of thesupporting plate in the horizontal position of the supporting plate thatit can be. freely moved by hand. This makes possible a direct correctionofthe horizontal position of the patient which may be desired in certaincases. g I 7 According to a further development of the present inventionan overpressure-valve is provided to avoid that the cylinder providedfor the heightmovement would be actuated when there is no load uponthe,supporting plate so that the plate would move upwardly withgreat speedand be damaged. Thisove'rpressure valve is provided in theconnectionbetween the cylindrical space causingthe height movementof thesup-' porting plate andthe corresponding instrumental valve; 1 itresponds to pressure exerted byweight upon the supporting plate andprovides an opening of theinstrume'ntal valve for the height movement ofthe support-ing plate only when this weight is present.

In a device having a removable supporting plate there 7 is the dangerthat the cylinder causing the heightmovement of the supporting platewill be actuated when the plate is not properly mounted, which can causedamage to the cylinder or the plate. According to a feature of thepresent invention thisdanger is avoided by the provision of safetyvalves at the bearings of the plate which permit an opening of theinstrumental'valv'e for the height movement of the supporting plate onlywhen the plate is properly'mounted.

According to another embodiment of the presentinvention a compressed airmotor is used as the driving element for the pressure producer of thehydraulic system and there are means actuated by the steering device forswitching the motor on and off. These means actuate the motor when oneof the steering members is operated and they switch it off at the end ofthe movement. This provides that the actuating element for the hydraulicdrive is operable by air pressure and not by electrical circuits whereinthe explosion danger can be avoided only with great exertion and notwith complete safety.

For operating tables which are used for example in conjunction withX-ray devices it is particularly important to keep freely available thegreatest possible section of the patient carrying plate at its bottomside. This requirement makes necessary a foot construction which shouldsave as much space as possible. According to yet another embodiment ofthe present invention this is attained by placing the hydraulic memberfor the height movement of the supporting plate inside a two partbox-like foot between its two parts, whereby one part carries thesupporting plate and is substantially vertically movable relatively tothe other part by the use of the hydraulic member. The division of thefoot extends along a shortened diagonal. There are two struts extendingparallel to each other and diagonally opposed to the division of the twofoot parts. These struts are swingably connected at both ends at arelative distance corresponding to about one half stroke with ends ofthe two foot parts. The hydraulic member is located between the twostruts preferably at their fixing points which are closest to each otherin the deepest position of the supporting plate. This constructionprovides a particularly compact structure of the foot with a largestroke at a low height of the table which is important for certain uses.In addition this construction has the advantage that it requires onlylittle precision during manufacture, that it does not need greatmounting expenditure and that its making is simple.

The invention will appear more clearly from the following detaileddescription when taken in connection with the accompanying drawingsshowing by way of example only, preferred embodiments of the inventiveidea.

In the drawings:

FIG. 1 is a front view of an operating table constructed in accordancewith the present invention.

FIG. 2 is a side view of the same table.

FIG. 3 is a circuit diagram of the steering system.

FIG. 4 illustrates diagrammatically the steering device for thehydraulic drive.

FIG. 5 is a front view of an operating table having a particularly spacesaving foot construction.

FIG. 1 shows the lower part of an operating table as consisting of acylinder-like foot casing l which is open on top and into which extendspiston-like a further casing 2 which is closed on top and is movablevertically relatively to the casing l. The cover of the casing 2 has acylindrical head 3 to which is fixed the frame 4 of the patientsupporting plate 5. A hydraulic member 8 is fixed on pins 6 and 7between the casings l and 2 and it causes a vertical relative movementof the two casings and thus the height movement of the supporting plate.Another hydraulic member 9 which causes the swinging movement of thesupporting plate 5 about the rotary axle 10, is located between thecasing 2 and the frame 4 and is fixed on pins 11, 12. The supportingplate 5 is movably mounted upon a slide system (not shown) which isfixed to the frame 4. A hydraulic member 13 is provided for thelongitudinal movement of the patient supporting plate 5 and is fixed onpins 14 and 15 between the frame 4 and the supporting plate 5.

FIG. 2 shows that a hydraulic member 18 is provided between the frame 4and the piston-like casing 2 upon pins 16 and 17 for the side tipping ofthe supporting plate about the rotary axle 19. A hydraulic member 20provided for the transverse movement of the supporting plate 5, is fixedon pins 21, 22 between the frame 4 and the supporting plate.

A central steering device 23 provided for steering the hydraulic membersis connected by compressed air conduits combined in a cable 24 with theelements of the hydraulic system which are to be actuated. The centralsteering device 23 can be placed upon a carriage (not shown), upon anydesired location of the apparatus itself or on a wall of the treatingroom. The cable 24 can be pulled screw-like in a manner similar to thatof a telephone cable.

FIG. 3 shows several steering members 25 to 32 combined in the centralsteering device 23, provided with corresponding pressure keys 33 to 40and connected with an outer compressed air container 41. The hydraulicmembers 8, l3 and 18 are actuated by instrumental valves 42, 43 and 44.The auxiliary valve 45 connected in parallel to the instrumental valve43 operates as a short circuit valve. The other component parts of thehydraulic system, including the steering device 46 for the hydraulicdrive shown in FIG. 4 and the valve unit 47 will be described later on.

By actuating one of the pressure keys 33 to 40 of the steering members25 to 32 compressed air will flow from the compressed air container 41through the corresponding connecting conduit to the actuated valve. If,for example, the pressure key 35 of the steering member 27 is actuated,then compressed air will reach through a two way valve 48 one of the twoinlets of an instrumental valve 44, so that the valve will be actuatedin such manner as to connect with each other the oil conduits 49 and 50,as well as the conduits 51 and 52 of the hydraulic member 18. At thesame time the two way valves 53, 54 and 55 connected in series in thevalve unit 47 are influenced by the conduit b (FIG. 4). This causescompressed air to reach a pressure amplifier 56, so that enough force isavailable for actuating the piston 57 which actuates a coupling rod 58.This switches on a compressed air motor 59 which drives an oil pump 60which can be arranged upon the instrument table or outside. Then oilflows from an oil tank 61 through the connecting conduit 49, theinstrument valve 44 and the conduit 50 into the hydraulic member 18causing the supporting plate 5 to carry out a tipping movement. Thereturning oil flows through the connecting conduits 52, the instrumentvalve 44 and the connecting conduit 51 back into the oil tank 61 (FIG.4), a choke valve 62 being provided for pressure regulation in theconduit 51. When supply of compressed air is interrupted by releasingthe pressure key 35 of the steering member 27, the instrument valve 44closes the flow of oil through the conduits 50, 52. Furthermore, the oilsupplying motor 59 is switched off due to lack of pressure in thepressure amplifier 56.

When the key 34 of the steering member 26 is pressed compressed air willreach the other inlet of the steering valve 44 through the two way valve63, so that oil conduits 49, 52 as well as 50 and 51 are connected witheach other. Furthermore compressed air reaches through the two way valve63 and the conduit 0 the pressure amplifier 56 which switches on themotor 59. This actuates the hydraulic member in the opposite directionto that above described, so that the supporting plate 5 returns to itsoriginal position.

The described operational example related to the tipping movement of thepatient supporting plate 5. In a similar manner is carried out theactuation of the hydraulic member 8 for the height movement and of thehydraulic member 9 for the longitudinal movement of the supporting plate5. It is possible to provide further hydraulic members and instrumentalvalves which would steer and produce other movements of the device in asimilar manner.

The steering member 25 is provided in the central steering unit 23 forautomatically finding a specific position of the patient supportingplate. By actuating the pressure key 33 of this steering membercompressed air will flow to four positioning valves 64 to 67. Thepositioning valves 64, 65 are connected through two way valves 48, 63 toone of the two steering inlets of the instrumental valve 43 and thepositioning valves 66, 67 are connected through two way valves 72, 73 toone of the two steering inlets of the instrumental valve 44. Thepositioning valves are so arranged that they can be switched off by lugs68 to 71 located upon the supporting plate 5 in the provided position ofthe patient supporting plate. When one of the table lugs, for examplethe lug 70, actuates the positioning valve 66 pertaining to it, thencompressed air is supplied on the one hand to the instrumental valve 44and on the other hand to the pressure amplifier 56 through the two wayvalve 48 in the already described manner, so that the hydraulic member18 begins to operate and the corresponding part, in this case thesupporting plate 5 will move until it reaches the'predeterminedposition. In this position the positioning valve 66 is switched off bythe lug 70 so that the supply of oil to the hydraulic member 18 throughthe instrument valve 44 influenced by the positioning valve 66 isinterrupted. The other positioning valves 64, 65, 67 operate in acorresponding manner.

The steering members 29, 30 with their pressure keys 37, 38 are suitablefor operating the instrument valve 43 and the hydraulic member 13, whichare provided for the longitudinal movement of the supporting plate 5.The two way valves 72, 73 operate in the same manner as the two wayvalves 48, 63 namely, they transmit An auxiliary valve 45 connected inparallel to the instrumental valve 43,is provided for the free movementby hand of the supporting plate in the horizontal position. By actuatingthe pressure key 36 of the steering member 28 compressed air is suppliedto the auxiliary valve 45, so that this valve becomes active andconnects with each other the two conduits 74, 75 of the hydraulic member13; This produces a pressure balance in the two cylindrical spaces 77,78 divided'by the piston 76 and provided in the hydraulic member 13 usedfor the longitudinal movement of the supporting plate 5, so that thepiston 76 and consequently the supporting plate 5 can be freely movablein the longitudinal direction.

It is often advantageous not to connect the supporting plate 5 firmlywith the apparatus but to make it removable. This facilitates theplacing of the patients in many cases. However, in such a constructionthere is the possibility that the supporting plate 5 will not liecorrectly upon its supports 85, 86. If in case of such an incorrectpositioning the stroke mechanism is actuated there is the danger thatthe supporting plate will tip over and the patient will suffer injuries.To prevent this safety valves 87, 88 are located upon the supportingpoints of the plate, which are switched into the connecting conduitbetween the steering member 32 and the overpressure valve 84. Only whenthese safety valves are actuated by the corresponding lugs 89, 90 afterthe placing of the plate 5 upon the supports 85, 86, there is acompressed air connection between the steering member 32 and theinstrument valve 42. Oth erwise the connection is interrupted.

To avoid that the speeds of the lowering movements of the supportingplate 5 be dependent upon the load carried by the plate throttle valves62, 91, 92 are provided in the conduits 51, 93 and 94 between theinstrument valves 42, 43, 44 and the oil tank 61.

FIG. 5 is a front view of a construction of the raising mechanism of thepatient supporting plate 5 which is different from that of FIG. 1. Inthis construction the box-shaped support of the device is divided alonga shortened diagonal 95 and thus consists of two parts 96, 97. The part96 is firmly connected with the ground plate 98, while the. part 97carries the supporting plate 5. The two parts are interconnected bystruts 99 and 100 extending diagonally in a direction opposed to that ofthe diagonal division of the parts. These two struts are locatedlongitudinally parallel to each other at a distance corresponding toabout one half of the stroke and are connected by supporting pins 101and 102 with the base part 96, and by supporting pins 103 and 104 withthe base part 97. The hydraulic member 8 is located between bearing pins102 and 103 located closest to each other in the illustrated deepestposition of the supporting plate 5.

If this member is actuated, a force is producedbetween the bearing pins102 and 103 so that the two struts move upwardly as a parallelogramabout the points 101 and 102. This will raise the supporting plate tothe desired extent. A comparison between the construction shown in FIG.1 and that shown in FIG. 5 shows clearly that the construction of FIG. 5permits a substantially higher raise. Furthermore the construction ofFIG. 5 has no sliding precision parts, but only generally used bearingpins which can be mounted in a simple and precise manner.

Parts similar in arrangement and function to those of FIG. 1 areprovided with the same reference numerals.

What is claimed is:

1. A medical device, comprising a plate for the patient, a casing, aframe pivotally connected with said casing and supporting said plate, atleast one hydraulic member connected with said frame for swinging saidframe, another hydraulic member connected with said casing forvertically moving at least a part of said casing, at least one thirdhydraulic member connected with said plate for longitudinally movingsaid plate, a plurality of instrumental valves, means operativelyconnecting one of said instrumental valves with the firstmentionedhydraulic member, means operatively connecting another one of saidinstrumental valves with the second-mentioned hydraulic member, meansoperatively connecting a third one of said instrumental valves with thethird-mentioned hydraulic member, a central steering device comprising aplurality of interconnected steering members, and separate pressure keysconnected with separate steering members; a compressed air containerconnected with all steering members, means operatively connecting one ofsaid steering members with the first-mentioned instrumental valve, meansoperatively connecting another one of said steering members with thesecond-mentioned instrumental valve, means operatively connecting athird one of said steering members with the third-mentioned instrumentalvalve, whereby said instrumental valves are actuated by gas from saidcompressed air container, a plurality of positioning valves connected toa steering member, a separate positioning valve being connected inparallel with a separate instrumental valve, and a plurality of lugs, aseparate lug being connected with each positioning valve for operatingthat valve, said lugs switching off said positioning valves in apredetermined position of said plate.

2. A device according to claim 1, wherein means connecting at least twoof said positioning valves to the instrumental valves are also connectedto at least two steering members to maintain the two positioning valveson opposite sides of the basic position of said frame.

3. A device according to claim 2, comprising means connected with one ofsaid steering members and said third-mentioned instrumental valve forshort-circuiting the third-mentioned instrumental valve to permit handmovement of said plate.

4. A device in accordance with claim 3, wherein the last-mentioned meansinclude an auxiliary valve and conduits connected with said valve ahdwith opposed sides of the third hydraulic member, said opposed sidesbeing separated by the piston of said hydraulic memher.

5. A device in accordance with claim 4, wherein means connecting thesecond-mentioned hydraulic member with the second-mentioned instrumentalvalve comprise an overpressure switch, an overpressure valve connectedwith said overpressure switch, and means connected with saidoverpressure switch and actuating it depending upon the pressure exertedby the weight of said plate, said overpressure switch actuating saidoverpressure valve only when this pressure is present, whereupon saidoverpressure valve will pennit opening of the second-mentionedinstrumental valve for the vertical movement of said casing.

6. A device in accordance with claim 4, wherein said frame comprisessupports engaging said plate, a separate safety valve connected witheach support, and means connecting said safety valves with thesecondmentioned instrumental valve, said safety valves opening thesecond-mentioned instrumental valve to permit movement of said plateonly when said plate is properly mounted.

7. A device in accordance with claim 1, having a hydraulic systemcomprising an oil pump, a compressed air motor driving said pump, acoupling rod connected with said motor, apiston connected with saidcoupling rod, a pressure amplifier connected with said piston, a valveunit comprising a plurality of valves interconnected in series andincluding a central valve connected with said pressure amplifier, andmeans connecting other valves of said plurality of valves with meansconnecting the first-mentioned, the secondmentioned and thethird-mentioned steering members with the first-mentioned,second-mentioned and thirdmentioned instrumental valves, whereby saidmotor is actuated when one of the steering members is actuated, saidmotor being switched off when the movement is terminated.

8. A device in accordance with claim 1, wherein said casing isbox-shaped and consists of two parts, one of said parts being fixed, thesecond-mentioned hydraulic member being located within said casing andconnected with both parts of the casing, the other one of said partscarrying said frame, the second-mentioned hydraulic member moving saidother part substantially vertically relatively to said one part.

9. A device in accordance with claim 8, wherein said two parts of thecasing are divided along short diagonal edges, two parallel strutslocated within said casing and extending through both parts in diagonaldirections substantially opposed to the direction of said diagonaledges, and pins mounted on both ends of each of said struts and fixed tothe casing, the second-mentioned hydraulic member having opposite endscarried by two of said pins which are closest to each other and fixed todifferent parts of the casing.

1. A medical device, comprising a plate for the patient, a casing, aframe pivotally connected with said casing and supporting said plate, atleast one hydraulic member connected with said frame for swinging saidframe, another hydraulic member connected with said casing forvertically moving at least a paRt of said casing, at least one thirdhydraulic member connected with said plate for longitudinally movingsaid plate, a plurality of instrumental valves, means operativelyconnecting one of said instrumental valves with the first-mentionedhydraulic member, means operatively connecting another one of saidinstrumental valves with the second-mentioned hydraulic member, meansoperatively connecting a third one of said instrumental valves with thethird-mentioned hydraulic member, a central steering device comprising aplurality of interconnected steering members, and separate pressure keysconnected with separate steering members; a compressed air containerconnected with all steering members, means operatively connecting one ofsaid steering members with the first-mentioned instrumental valve, meansoperatively connecting another one of said steering members with thesecond-mentioned instrumental valve, means operatively connecting athird one of said steering members with the thirdmentioned instrumentalvalve, whereby said instrumental valves are actuated by gas from saidcompressed air container, a plurality of positioning valves connected toa steering member, a separate positioning valve being connected inparallel with a separate instrumental valve, and a plurality of lugs, aseparate lug being connected with each positioning valve for operatingthat valve, said lugs switching off said positioning valves in apredetermined position of said plate.
 2. A device according to claim 1,wherein means connecting at least two of said positioning valves to theinstrumental valves are also connected to at least two steering membersto maintain the two positioning valves on opposite sides of the basicposition of said frame.
 3. A device according to claim 2, comprisingmeans connected with one of said steering members and saidthird-mentioned instrumental valve for short-circuiting thethird-mentioned instrumental valve to permit hand movement of saidplate.
 4. A device in accordance with claim 3, wherein thelast-mentioned means include an auxiliary valve and conduits connectedwith said valve and with opposed sides of the third hydraulic member,said opposed sides being separated by the piston of said hydraulicmember.
 5. A device in accordance with claim 4, wherein means connectingthe second-mentioned hydraulic member with the second-mentionedinstrumental valve comprise an overpressure switch, an overpressurevalve connected with said overpressure switch, and means connected withsaid overpressure switch and actuating it depending upon the pressureexerted by the weight of said plate, said overpressure switch actuatingsaid overpressure valve only when this pressure is present, whereuponsaid overpressure valve will permit opening of the second-mentionedinstrumental valve for the vertical movement of said casing.
 6. A devicein accordance with claim 4, wherein said frame comprises supportsengaging said plate, a separate safety valve connected with eachsupport, and means connecting said safety valves with thesecond-mentioned instrumental valve, said safety valves opening thesecond-mentioned instrumental valve to permit movement of said plateonly when said plate is properly mounted.
 7. A device in accordance withclaim 1, having a hydraulic system comprising an oil pump, a compressedair motor driving said pump, a coupling rod connected with said motor, apiston connected with said coupling rod, a pressure amplifier connectedwith said piston, a valve unit comprising a plurality of valvesinterconnected in series and including a central valve connected withsaid pressure amplifier, and means connecting other valves of saidplurality of valves with means connecting the first-mentioned, thesecond-mentioned and the third-mentioned steering members with thefirst-mentioned, second-mentioned and third-mentioned instrumentalvalves, whereby said motor is actuated when one of the steering membersis actuated, said motor being switched off when the movement isTerminated.
 8. A device in accordance with claim 1, wherein said casingis box-shaped and consists of two parts, one of said parts being fixed,the second-mentioned hydraulic member being located within said casingand connected with both parts of the casing, the other one of said partscarrying said frame, the second-mentioned hydraulic member moving saidother part substantially vertically relatively to said one part.
 9. Adevice in accordance with claim 8, wherein said two parts of the casingare divided along short diagonal edges, two parallel struts locatedwithin said casing and extending through both parts in diagonaldirections substantially opposed to the direction of said diagonaledges, and pins mounted on both ends of each of said struts and fixed tothe casing, the second-mentioned hydraulic member having opposite endscarried by two of said pins which are closest to each other and fixed todifferent parts of the casing.